VIRUSfighter VISTA 5.99 If you need an antivirus program for Windows Vista, VIRUSfighter is for you. VIRUSfighter is a user-friendly antivirus program for Windows Vista that is easy to install on your computer and gives you the best protection you can get. VIRUSfighter is your protection against your computer being destroyed by a virus. The program is easy to install, and then runs discreetly in the background, watching for threats.